In radios, particularly mobile radios such as a frequency modulation (FM) radio, signal quality can become impaired in the presence of multipath fading. Multipath fading is an impairment commonly observed in which multiple versions of the transmitted signal arrive at the receiver with different phase, delay and attenuation levels, resulting in destructive interference at the receiver. This destructive interference can negatively impact the quality of the radio output.
Existing techniques to address fading issues include so-called antenna diversity techniques in which multiple antennas, typically two such antennas, are connected to the same radio receiver. and the output of one of the multiple antennas is selected for processing and demodulation. Different varieties of such diversity techniques exist, but all typically include multiple antennas that may be positioned at different phases such that if one of the antennas suffers from fading, the other antenna is unaffected. Typically, selection between the two antenna paths is based on a monitored metric of the incoming signal from the various antennas. However, such techniques are suboptimal.